As environmental concerns have increased over the last thirty years, the need to reprocess paper products received by waste handling companies has intensified. In order to improve efficiency in recycling activities, companies have found it necessary to divide the paper received into several different homogeneous groups. In particular, the separation of cardboard from office paper and computer printout waste is very valuable.
Early efforts at achieving this separation used manual systems. These systems employed slow moving conveyors of five to six feet in width for moving waste through a work area. Workers positioned along a conveyor could then manually remove cardboard and place it in a separate container. These types of systems have many drawbacks. First, the systems are extremely slow, constrained by the limitation of human labor that can be concentrated around the line. Second, the quality of separation depends upon the diligence of the human labor employed. As with many repetitious jobs, some degree of "missed" cardboard results. Third, the size of the line system is quite large, requiring a very wide belt and a full work area around it. Finally, the system was not easily reconfigurable to handle higher or lower throughput demands.
The mechanization of the manual system addressed some of these drawbacks. Current machines have included a configuration of a series of rotors. These rotors move the waste stream along. As the stream moves, paper products fall through the rotors, separating the paper from the cardboard. With these machines, the reliance element on human labor has been reduced. This reduction has vastly increased the speed of the system and decreased the dedicated work space required. However, machines have also increased some of the problems of the manual system. Particularly, current machines are typically not as reliable in their separation as manual labor. In current machines, the low quality of separation continues to require manual monitoring of the output for missed cardboard or paper. Beyond raw separation problems, current rotor based machines have also been ineffective in separating paper which rests on top of a piece of cardboard. For example, a sheet of cardboard may pass over the rotors of the separating machine with a large stack of accordion-style computer paper sitting on the cardboard. The entire stack, perhaps thousands of sheets, rides on the cardboard to the end of the disc rotors to be dumped on the cardboard discharge pile. A similar problem exists with cardboard boxes having paper inside the boxes. Although paper is intended to drop through the separating disc rotors, in this case, the box, with all the paper inside, is carried to the cardboard discharge pile. Additionally, prior art separator machines are typically configured for a specific type of operation and cannot be easily adapted to changes in the mix of paper and cardboard in the input stream. Finally, prior art rotor machines have been subject to mechanical failure due to binding of paper from the input stream around either the rotors or the rotor bearings. A means is needed to remove paper from the top of cardboard sheets and to remove paper from the interior of cardboard boxes.